title: Effect of short- and long-term physical activities on circulating granin protein levels.
abstract: BACKGROUND
  The classic chromogranin-secretogranin (granin) proteins are produced in the myocardium and throughout the neuroendocrine system, but while chromogranin (Cg) A and B levels are high in the adrenal medulla, secretogranin (Sg) II production is higher in the pituitary gland. Whether these differences may influence the response to physical activity is not known.
  
  
  METHODS
  We measured circulating granin proteins during (1) a short-term maximal bicycle exercise stress test and (2) a 7 day military ranger course of continuous physical activity and sleep and energy deprivation.
  
  
  RESULTS
  In 9 healthy subjects performing the exercise stress test (7 male, age 45±5 y [mean±SEM], duration 10.13±1.14 min), CgB levels increased from before to immediately after the test: 1.20±0.12 vs. 1.45±0.09 nmol/L, p=0.013. Metabolic equivalents, representing an index of performed work, were closely associated with the change (∆) in CgB levels during stress testing and explained 74% of the variability in ∆CgB levels (p=0.004). CgA and SgII levels were not increased after exercise stress testing. In the second cohort of 8 male subjects (age 25±1 y) participating in the ranger course, CgB levels increased from day 1 and were significantly elevated on days 5 and 7. CgA also increased gradually with levels significantly elevated on day 7, while SgII was markedly increased on day 5 whereas levels on days 3 and 7 were unchanged compared to baseline levels.
  
  
  CONCLUSIONS
  We demonstrate a heterogeneous response to short- and long-term physical activities among circulating granin proteins with the most potent effect on CgB levels.
authors.affiliation: Department of Cardiology, Division of Medicine, Akershus University Hospital, Lørenskog, Norway; Center for Heart Failure Research and K.G. Jebsen Cardiac Research Centre, Institute of Clinical Medicine, University of Oslo, Oslo, Norway. Electronic address: helge.rosjo@medisin.uio.no.
authors.forename: Helge
authors.initials: H
authors.lastname: Røsjø
authors.forename: Per-Kristian
authors.initials: PK
authors.lastname: Opstad
authors.forename: Jon Erik
authors.initials: JE
authors.lastname: Hoff
authors.forename: Kristin
authors.initials: K
authors.lastname: Godang
authors.forename: Geir
authors.initials: G
authors.lastname: Christensen
authors.forename: Mats
authors.initials: M
authors.lastname: Stridsberg
authors.forename: Torbjørn
authors.initials: T
authors.lastname: Omland
mesh_terms: D000328:Adult; D053379:Chromogranin A / Q000097:blood*; D053378:Chromogranin B / Q000097:blood*; D002149:Energy Intake; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood; D010446:Peptide Fragments / Q000097:blood; D005082:Physical Exertion; D053381:Secretogranin II / Q000097:blood*; D012892:Sleep Deprivation / Q000097:blood; D055815:Young Adult
chemical_list: D053379:Chromogranin A; D053378:Chromogranin B; D010446:Peptide Fragments; D053381:Secretogranin II; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain
keywords: BMI; Catecholamines; CgA; CgB; Chromogranin A; Chromogranin B; ECG; HPLC; METs; N-terminal pro-B-type natriuretic peptide; NT-proBNP; Physical activity; RIA; SEM; Secretogranin II; SgII; VO(2) max; body mass index; chromogranin A; chromogranin B; electrocardiogram; high-performance liquid chromatography; mRNA; maximal oxygen uptake; messenger-RNA; metabolic equivalents; radioimmunoassay; secretogranin II; standard error of mean